Based on the hydrogen-binding to the traps in the bulk SiO2, a mechanism was proposed to explain the very short response time on the device with the ultra-thin SiO2.
The measured non-specific binding (Fig. 5) includes both the radioligand trapped to the lipid membrane and to other membrane proteins and possible binding to the plastic of Eppendorf tubes.
One group of molecules act as ligand binding traps to sequester the ligand, examples of which include α2 macroglobulin, which binds TGF-β, and follistatin, which binds activin A. The other group of molecules are membrane-bound co-receptors which promote ligand binding to the receptors.
In previous calorimetry experiments, the ΔS of tryptophan binding to TRAP was found to be zero at approximately 287 K, becoming increasingly negative as the temperature was increased [ 21].
Tryptophan binding to TRAP shows only a small change in the Gibbs free energy of binding over a 25 50 °C range, with binding becoming gradually weaker as the temperature increases [ 21].
This is interesting as Thr is known to be important for tryptophan binding to TRAP [ 39] and a hydrogen bond is found between tryptophan and the carbonyl oxygen of Thr in tryptophan-bound crystal structures.
In prokaryotes, factors that package DNA, such as HU proteins, may control supercoiling by binding to DNA and trapping the free energy of supercoiling as writhe and subsequently releasing it through controlled dissociation [ 3,4].
Naringenin enhanced the binding of the LXRα LBD to the Trap 220/Drip-2 220/Drip-2or moderately, yet significantly, in a dose-dependent manner reaching 38.0%±2.8% activation (Fig. 2b) comoderatelythe well-studied LXRα agonist, TO901317 (Fig. 2c).
This can be explained by secondary recruitment of SG proteins via binding to RNA molecules trapped in the FAs by interaction with RNA-binding domains of FUS.
